Andros, or Andro (Greek: Άνδρος) is the northernmost island of the GreekCycladesarchipelago, approximately 10 km (6 mi) south east of Euboea, and about 3 km (2 mi) north of Tinos. It is nearly 40 km (25 mi) long, and its greatest breadth is 16 km (10 mi). Its surface is for the most part mountainous, with many fruitful and well-watered valleys. The area is 380 km2 (147 sq mi). The largest towns are Andros (town), Gávrio, Bátsi, and Órmos Korthíou.

The island is famous for its Sariza spring at Apoikia where the water comes out of a lionhead. Palaeopolis, the ancient capital, was built into a steep hillside, and the breakwater of its harbor can still be seen underwater.

During the Final Neolithic (over 5,000 years ago), Andros had a fortified village on its west coast, which archaeologists have named Strofilias, after the plateau on which it was built. Strofilas was related to the "Attica-Kephala" culture, and predates the Cycladic culture of the Bronze Age. It was an important maritime center and one of the earliest examples of fortification in Greece. It is notable for rock carvings on its walls, which include animals such as jackals, goats, deer, fish and dolphins, as well as a depiction of a flotilla of ships.[1] The island in ancient times contained an Ionian population, perhaps with an admixture of Thracian ancestry.[citation needed] Though originally dependent on Eretria, by the 7th century BC it had become sufficiently prosperous to send out several colonies, to Chalcidice (Acanthus, Stageira, Argilus, Sane). The ruins of Palaeopolis, the ancient capital, are on the west coast; the town possessed a famous temple, dedicated to Dionysus. In 480 BC, it supplied ships to Xerxes and was subsequently harried by the Greek fleet. Though enrolled in the Delian League it remained disaffected towards Athens, and in 477 had to be coerced by the establishment of a cleruchy on the island; nevertheless, in 411 Andros proclaimed its freedom, and in 408 withstood an Athenian attack. As a member of the second Delian League it was again controlled by a garrison and an archon. In the Hellenistic period, Andros was contended for as a frontier-post by the two naval powers of the Aegean Sea, Macedon and Ptolemaic Egypt. In 333, it received a Macedonian garrison from Antipater; in 308 it was freed by Ptolemy I of Egypt. In the Chremonidean War (266-263) it passed again to Macedon after a battle fought off its shores. In 200, it was captured by a combined Roman, Pergamene and Rhodian fleet, and remained a possession of the Kingdom of Pergamon until the dissolution of that kingdom in 133 BC. Before falling under Turkish rule, Andros was governed by the families Zeno and Sommaripa under Venetian protection from 1207 till 1566 (see: Duchy of the Archipelago). Subsequently, the island again came under direct Ottoman rule. After a few centuries, the Cyclades joined the rest of Greece in 1821.

On May 10, 1821, Theophilos Kairis, one of the leading intellectuals of the Greek Revolution, declared the War of Independence by raising the Greek flag at the picturesque cliffside church of St George: at this time, a famous heartfelt speech, or "ritoras" (ρήτορας), inspired shipowners and merchants to contribute funds to build a Greek Navy to combat the Ottomans.

Andros is a separate regional unit of the South Aegean region, and the only municipality of the regional unit. As part of the 2011 Kallikratis government reform, the regional unit Andros was created out of part of the former Cyclades Prefecture. At the same reform, the current municipality Andros was created out of the 3 former municipalities:[2]

The province of Andros (Greek: Επαρχία Άνδρου) was one of the provinces of the Cyclades Prefecture. Its territory corresponded with that of the current regional unit Andros.[3] It was abolished in 2006.

Andros, the capital, on the east coast, contained about 2,000 inhabitants in 1900. The island had about 18,000 inhabitants in (1900). The 1991 census read 8,781. According to the latest Greek census of 2011, the town of Andros still contained 1,665 inhabitants, and the island's total was 9,221. The island is composed of the municipal units of Andros (town) (pop. 3,901), Korthio (pop. 1,948), and Ydrousa (pop. 3,372). The north of Andros has a small Arvanite community. The name of the island in Arvanitika is Ε̰νdρα, Ëndra.[4]